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排序方式: 共有616条查询结果,搜索用时 31 毫秒
511.
在分析伞降高度选择影响因素的基础上,研究了敌反空降防空火力对伞降高度选择的影响,给出了各类防空火力对不同高度实施空降时运输机和伞兵毁伤数的计算公式;基于伞降高度选择原则建立了伞降高度选择模型.通过实例证明了模型的合理性,可为空降作战决策提供参考依据. 相似文献
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介绍了安全轮胎的定义和主要技术类型,根据车辆防护性对安全轮胎的要求,对考核轮胎防护性的试验评价方法进行了研究,提出了相应的道路行驶试验方法。为了获得轮胎防护性的量化特征,建立了轮胎防护性评价指数模型,为评价轮胎防护性能提供了一种分析方法。 相似文献
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Nicolas Groffman 《Defense & Security Analysis》2016,32(2):144-162
India and China both have powerful spy networks; completely different in their approaches to espionage; both effective against their perceived enemies. China focuses first on internal threats, on Taiwan and Hong Kong, and then the US and Japan. India’s defense policy focuses on Pakistan and internal terrorist threats, and then on China. In reality, however, when it comes to spying on each other, both China and India suffer from incompetence and apathy – which endangers both their own security and regional stability. This article looks at how they spy on each other, and asks why and how they need to improve. The narrative also touches upon some of the individuals who are waging the spy war, from India’s wily spymaster Ajit Doval down to junior Chinese agents such as Wang Qing and Pema Tsering. The two countries are not friends. They have the largest territorial dispute in the world on their hands, covering an area the size of North Korea, and they have large armies facing each other along 4000 kilometers of frontier. But they also lay claim to the world’s two oldest and richest civilizations, with a rich history of exchange, and now with a combined population of 2.6 billion people and more than a quarter of the world’s economic output. If they cooperated, they could solve many of the world’s problems; but if they lurch into conflict, the potential consequences are terrifying to contemplate. Unfortunately, despite their geographical closeness, they do not know much about each other. They have few cultural interchanges, little diplomacy, few trade missions. They do not watch each other’s films, read each other’s books or listen to each other’s music. Chinese tourists would rather fly to New Zealand for their holidays than cross the border to India, and Indian students would rather study in Europe than China. China and India are neighbors that barely talk to each other. Most significantly, they do not spy on each competently. For countries that do not interact socially, defensive understanding is important for security – but China prefers the glamor of facing up to its Pacific and other maritime rivals such as the US and Japan. India, for its part, does talk a great deal about the China threat, but its resources and expertise are wrapped up in controlling its security threat from Pakistan and the Islamic world. When China and India do try to spy on each other, it is often without the benefit of a long-term focus or understanding. India has some very skilled operatives within the Research and Analysis Wing, but few that specialize in China. China has an enormous pool of resources spread across several government departments, including the Ministry of Public Security, and also has extensive facilities and manpower in the Joint Staff Department of the Central Military Commission (the JSD) and the new Strategic Support Force (the SSF). However, China’s intelligence services generally behave as if India is not worth spying on. Given that the two countries do not have the cultural or political machinery in place to understand each other, espionage and intelligence gathering is vital to ensure that miscalculations do not take place. This has been apparent over the last few years in stand-offs in the Himalaya, as well as top-level suspicions on each side about a variety of subjects including terrorism, covert operations in Sri Lanka and Burma, and the two countries’ nuclear weapons programs. Both countries do occasionally make efforts in espionage against each other, especially during sensitive periods such as the mountain stand-offs of 2014 and 2013 and during policy developments in nuclear warfare. In this article the author looks at actual spying incidents between the two countries, their methodologies, their staff, their technical capabilities, and how the act of spying, which is usually viewed as intrinsically adversarial, can be a force for good. The article relies on interviews with actual participants in intelligence from both countries as well as extensive use of contemporary online sources, and secondary analysis by both military and academic experts from China, India and NATO countries. 相似文献
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Darrell Driver 《Defense & Security Analysis》2016,32(1):4-18
The US role in the North Atlantic Treaty Organization (NATO) Alliance is a 65-year history of retrenchment and renewal. When Washington has sought a retrenchment from the world, it traditionally increased burden sharing pressure on Europe to do more. During times of increased global ambition, the USA reaffirmed its traditional leadership role in the Alliance and its commitment to NATO effectiveness and relevance. This cycle of NATO retrenchment and renewal, however, is halting. Though the USA will continue to go through periods of relative increases and decreases in security policy ambition, signs point to a permanent defense and security retrenchment in Europe. Germany is the ally singularly capable of filling the resulting security gap. If NATO is to avoid the drift toward irrelevance many critics have predicted, Germany will need to cast off old inhibitions toward security and defense leadership. These trends and their implications for NATO's future are explored through historical case studies and the shifting contemporary security environment. 相似文献
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Validation of a strategy for harbor defense based on the use of a min‐max algorithm receding horizon control law 下载免费PDF全文
We present a validation of a centralized feedback control law for robotic or partially robotic water craft whose task is to defend a harbor from an intruding fleet of water craft. Our work was motivated by the need to provide harbor defenses against hostile, possibly suicidal intruders, preferably using unmanned craft to limit potential casualties. Our feedback control law is a sample‐data receding horizon control law, which requires the solution of a complex max‐min problem at the start of each sample time. In developing this control law, we had to deal with three challenges. The first was to develop a max‐min problem that captures realistically the nature of the defense‐intrusion game. The second was to ensure the solution of this max‐min problem can be accomplished in a small fraction of the sample time that would be needed to control a possibly fast moving craft. The third, to which this article is dedicated, was to validate the effectiveness of our control law first through computer simulations pitting a computer against a computer or a computer against a human, then through the use of model hovercraft in a laboratory, and finally on the Chesapeake Bay, using Yard Patrol boats. © 2016 Wiley Periodicals, Inc. Naval Research Logistics 63: 247–259, 2016 相似文献
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Tai Ming Cheung 《战略研究杂志》2016,39(5-6):728-761
ABSTRACTChina’s defense science, technology, and industrial system has been undergoing a far-reaching transformation over the past two decades and the single biggest factor behind this turnaround is the role of external technology and knowledge transfers and the defense industry’s improving ability to absorb these inputs and convert into localized output. China is pursuing an intensive campaign to obtain defense and dual-use civil–military foreign technology transfers using a wide variety of means, which is explored in this article. 相似文献
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